Fire fuse link



June 1s, 19574 T. BARNES 2,796,494

FIRE FUSE'. LINK Filed March 5, 1956 INVENTOR I'aylajalms/ ATTORNEYUnited StatCS Patent iice Y 2,796,494 Patented June 18, 1957 FIRE FUSELINK Taylor Barnes, Shreveport, La., assignor to Bar-Brook ManufacturingCo., Inc., Shreveport, La.

Application March 5, l1956 Serial No. 569,514 9 Claims. (C1. 20o- 142)This Vinvention relates to re fuse links,i.particularly to.theconnecting -solder type which will melt in a predetermined time, apredetermined temperature and at a predetermined pressure or force. 1

The ksubject invention has Amany uses as key lock kickoutfor ire fusesprinklers, duct'work systems, in fact in any given location, `wherevera ktemperature responsive circuit closer is krequired `for home Aorbuilding to increase the security of the occupants and users of the homeor building. Obviously, the present apparatus may function to operate asprinkler system or any of the many types of alarms.

'The present invention is primarily ldesigned kfor use with a switch boxhaving a built-in momentary contact, spring loaded to Off position andhaving an easily removablecover for ready access to the wiring .withoutthe necessity of dismantling the vfuse ,link or the switch assembly.

`It is contemplated that the approved type of bonding material rbe usedthat meets the requirements of .the Bureaupof Standards for ythe meltingpoint of materials,

Figure 4 is a plan lView `of the cylindrical key, while Figure 5 is anend view of the same.

In the drawings where like reference characters denote like parts, theconnecting fire fuse link comprises two overlapping electrolyticallytinned members 10 and 12. The specific material used is yellow brass,V.062 inch thick, which are tin plated before assembly. The opposedouterends 14 and 16 are of general circular formation and are providedwith central apertures18 and 20.

The aperture 18 is adapted to'be lreceived on a threaded post of aswitch boxeassembly, not shown, while the aperture 20 is engaged by aswitch lever opposed from said post. The members 10 and 12 have reversedraised circular portions 22 and` 24 while only the circular portion 22has an opening26 which serves as a gas vent. It is to be noticed thatthe overlapping members 10 and 12 have reversed embossments 28 and 30`in the semi-circular ends 14 and 16 while the inner ends of the membersare curved at 32 and 34.

In Figures 2 and 3 it will be observed that companion half-pockets 36and38 are formed by the reversed raised central portions. lnterposedbetween the two overlapping members 10 and 12 is a strip of solder lm40, from .002 to .G04 inch in thickness, terminating yat the opposedends 32 .and 34. Adapted to `be encased in the formed pocket .36. 38 isa loosely contained slug or key 42, preferably cylindrical.

The fire fuse link is tinned electrolytically for better solder adhesionand increased corrosion resistance. The solder is to be made in twotypes, one melts at 1'35 degrees Fahrenheit, which is required bysomeStates; the other metals ,or waxes, at the standard or acceptedconditions establishedby their code standards, namely `tests inaccepted21`2 and 32 degrees Fahrenheit or in the equivalent centigradescale. Y n y With respect to other material qualications, `theconnectinglinks have been tinned electrolytically for better solder adhesion andincreased corrosion resistance. The solder mayrbe yof :twoltypes thatwill melt at '113-5 or 165 degrees Fahrenheit. f

In addition to the above noted usesv, the link is also adapted forimportant utilization inconnection with attic fan shutters, doors,l aswell as with conventional warning devices.

It is an object of my invention to provide a connecting link foroperating circuit closers at a predetermined temperature.

Another objective is to provide an overlapping connecting link that willhold any specified strength, weight or pull, dependent upon the sizelink used.

A further object is to arrange for the link melting point at the desiredtemperature through the use of approved bonding material, metallic orotherwise.

An additional object is to provide a connecting key lock constructionwhich will enable an immediate and positive jacking action with respectto the overlapping link members and the loosely contained key lock.

These and other objects made apparent during the further progress of thespecification are accomplished by means of the apparatus describedherein; a full and complete understanding of my invention beingfacilitated by reference to the drawings herein, in which,

Figure l is a top plan View of the connecting link.

Figure 2 is a sectional view taken on the line 2 2 of Figure l.

Figure 3 is a similar sectional view taken at the time of the separationof the two overlapping members.

melts at 165 degrees, Fahrenheit, a requisite in the majority of statesand is considered to be acceptable for all service use such as on fansand blowers.

lt can also be appreciated the switch utilized maybe designed forOnloadedWpurposes for use in connection with re alarms, signal lights,signal bells and other safety mechanisms. .Dueto the uses yof thespecific fuse linkwith the suggested typeofjswitch in -this developmenta faster acting'operation has been accomplished.

There is nolag or delay `when temperature has reached y the meltingpoint of `the' solder and the jacking action of the `small cylindricalrkey obtained springs apart the two halves of ,the fuse link. Thisresultant Aaction is clearly defined` in Figure3 `where the keyor-slugis shown tilted with the ,two lpreviously lfused halvesl of thelink separated. It can be understood that when the present device issubjected to tension the relatively longitudinal movement of the membersis converted into transverse separation of the two half sections.Because of this and the abutting relationship of the two members withthe loosely contained key or slug the tilting or jacking action isaccomplished.

From the above it will be apparent that the strip of solder iilm isdesigned to melt at a predetermined temperature and pressure and at apredetermined time. The connecting link may be constructed to hold anyspecified strength, weight or pull, dependent upon the size used.

The melting point temperature effectiveness is acquired by usingapproved Bureau of Standards bonding material, metallic, waxes orotherwise in accordance with their established standards, namely 212 or32 degrees Fahrenheit, or equivalent centigrade scale. The subject linkadapted to be actuated by the temperature under standard conditions hasthe approval of the Underwriters Laboratory, such approval given at and165 degrees Fahrenheit.

In addition to operation in connection with attic fan shutters andswitches, the link is adaptable for use on duct work, doors andconventional safety warning devices, or wherever time operation of thedevices is required and manual replacement is involved.

Various changes and modifications may be made in the size, shape andarrangement of the connecting lire fuse llink without departingfromVthe-spirit of the invention or scope of the appended claims.

What is claimed is:

1. A connecting fuse link subjected to tension comprising twooverlapping members fusibly connected and means between said members forjacking apart said members upon'fusing of saidfusible connection whilesaid members are subjected to tension, and'means comprising prisingreversed raised central portions on the outer surreversed raised centralportions on said members wherev byea pocket is formed adapted to receivea key. Y

2. A connecting fuse link subjected'to tension cornprising twooverlapping members fusibly connected and means between said two membersforl converting relatively longitudinal movement of vsaid members intotrans* verse separation thereof upon fusing of said fusible connectionwhile said members are subjected to tension, said means comprisingreversed raised central portions on said members whereby a pocket isformed adapted to receive a key, and said key being approximately of thesame formation as theinner walls of said pocket whereby said key may beloosely received therein.

3. A connecting fuse link subjected to tension comprising twooverlapping membersrfusibly connected and means between said members forjacking apart said members upon fusing of said fusible connection whilesaid members are subjected to tension, means comprising reversed raisedcentral portions on said members whereby a pocket is formed adapted toreceive a key, and said key being approximately of the same formation asthe inner walls of said pocket whereby said key may be loosely receivedtherein.v i

4. A connecting fuse link subjected to tension comprising twooverlapping members fusibly connected and means between said two membersfor converting relatively longitudinal movement of said members intotransverse separation thereof upon fusing of said fusible connectionwhile said members are subjected to tension, said means comprisingreversed raised central portions on the outer surfaces of said members:whereby a pocket is formed, afloose keyfreceivedy therein, said keyadapted to tilt and in abutment with said two members.

5. A connecting fuse link subjected yto tension com* prising twooverlapping members fusibly connected and means between said two membersfor jacking .apart said members upon fusing of said fusible connectionwhile said members are subjected to tension, said means comfaces of saidmembers whereby a pocket is formed, a loose slug received therein, saidslug adapted to tilt and in abutment with said two members.

6. A connecting fuse link subjected to tension comprising twooverlapping members fusibly connected and means between said two membersfor converting relatively longitudinal movement of said members intotransverse separation thereof upon fusing of said fusible connectionwhile said members are subjected to tension, and said means comprisingreversed central portions raised above the plane of the respective outersurfaces of said members whereby a pocket is formed to receive a key,and a gas vent disposed in the raised portion of the upper overlappingVmember.

7. A connecting fuse link subjected to tension comprising twooverlapping members fusibly connected and means between said members forjacking apart said members upon fusing of said fusible connection whilesaid members are subjected to` tension, means comprising reversed raisedcentral portions on said members whereby a pocket is formed adapted toreceive a tiltable key, and a gas vent disposed in the raised .portionof the upper overlapping member. f

8. A connecting fuse'link subjected to tension comprising twooverlapping members fusibly connected and means between said two membersfor converting relatively longitudinal movement of said members intotransverse separation thereof upon fusing of said fusible connectionwhile said members are subjected to tension, and spaced embossmentsformed in the opposed ends of said members whereby better clearance ofsaid fusible connection is maintained.

9. A connecting fuse link subjected to tension comprising twooverlapping members fusibly connected and means between said two membersfor converting relatively longitudinal movement of said members intotransverse separation thereof upon fusing of said fusible connectionwhile said members are subjected to tension, said means comprisingreversed central portions raised above the plane of the prospectiveouter surfaces of said members whereby a pocket isformed adapted toreceive a key, and spaced embossments formed in the opposed ends of saidmembers whereby better clearance of said fusible connectionis'maintained.

l References Cited in the leof this patent `UNITED STATES PATENTS

